Computer hard disks typically contain a protective, or overcoat, layer, above the magnetic layer. The overcoat layer is made of a highly wear-resistance material and is subject to direct wear resulting from frictional contact with the magnetic head so as to sacrificially protect the magnetic layer.
Recently, laser texturing techniques have been developed and utilized for high-performance, particularly low-flying-height, magnetic disks to form laser zone textures including the overcoat layer. Disks with laser zone texture often can offer the advantages of relatively low manufacturing costs as well as high precision control of disk surface topography and zone position.
Most of the published works on laser zone texture techniques have focused on optimizing the laser pulse width, spot size, pulse energy, and the effects the changes of these parameters on the formation of various bump shapes and bump heights. While these studies have provided very useful information regarding tribological performance in CSS testing and glide avalanche predictions and experiments, no study has been reported in the prior art which would deal with providing a tool for a quantitative description of wear characteristics for the laser zone textured bumps. A better understanding of the wear characteristic will aid the design of better laser textured bumps and improve the service of magnetic recording disks.